Kawasaki disease is a rare condition in children that involves inflammation of the blood vessels.

Kawasaki disease occurs most frequently in Japan, where the disease was first discovered. In the United States, after congenital heart defects, Kawasaki disease is the leading cause of heart disease in children. Most of these patients are younger than age 5. The disease occurs more often in boys than in girls.

Kawasaki disease is a poorly understood illness. The cause has not been determined. It may be an autoimmune disorder. The disorder affects the mucus membranes, lymph nodes, walls of the blood vessels, and the heart.

Kawasaki disease can cause inflammation of blood vessels in the arteries, especially the coronary arteries. This inflammation can lead to aneurysms. An aneurysm can lead to a heart attack, even in young children, although this is rare.